A water removal and adsorption integrated enrichment device and method

Abstract

The application relates to a water-removing and adsorbing integrated enrichment device and method, and the device comprises a three-way valve, an enrichment cavity, a switch valve and a time-of-flight mass spectrometer, and the devices are sequentially connected through pipelines; the enrichment cavity comprises a heating and heat-insulating layer, adsorbing material and a Nafion pipe; the heating and heat-insulating layer and the Nafion pipe are located in the interior of the enrichment cavity, and the adsorbing material is located in the interlayer between the heating and heat-insulating layer and the Nafion pipe. The application can realize online water removal and enrichment of trace substances in the environment, the device is small and simple to operate. The device and method are very novel, water removal is integrated in the enrichment device to avoid the influence of the environment on sample detection, and qualitative and quantitative analysis of the sample is facilitated.

Description

Technical Field

[0001] This invention specifically relates to an enrichment device and method that integrates water removal and adsorption. Background Technology

[0002] With rapid societal development and rising living standards, people are increasingly concerned about environmental pollution. Volatile organic compounds (VOCs), in particular, have garnered significant attention due to their high toxicity, harmfulness, and, in some cases, carcinogenic, teratogenic, and mutagenic properties. Therefore, online monitoring of VOCs in the environment has become crucial. However, the concentration of VOCs in the environment is often very low, making direct detection by analytical instruments difficult. This necessitates additional pretreatment methods, such as enrichment to concentrate the substances before resorption and injection, enabling online monitoring of trace amounts. Membrane mass spectrometry, commonly used in the literature, employs a membrane device for sample introduction, enabling rapid detection of trace VOCs in the environment. It is widely applied for rapid online detection of trace VOCs. The sample operates on the principle of permeation-diffusion-adsorption; the gas is first adsorbed onto the membrane surface, then diffuses within the membrane, and finally desorbs onto the mass spectrometer on the other side of the membrane. The operation is simple, and combined with a water removal device, interference is effectively eliminated. It offers high sensitivity, with a detection limit reaching 10. -9 (V / V) order of magnitude. Among them, the most commonly used enrichment membrane for membrane sampling is the silicone rubber organic membrane (PDMS). When a gas sample is introduced, the pressure difference caused by the difference in gas pressure on both sides of the membrane drives the volatile organic compounds in the sample to disperse in the membrane due to their different solubilities. Summary of the Invention

[0003] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0004] An integrated water removal and adsorption enrichment device includes an enrichment chamber and a time-of-flight mass spectrometer. The inner layer of the enrichment chamber is provided with a Nafion tube, the middle layer with a heating and insulation layer, and an adsorbent material within the interlayer between the heating and insulation layer and the Nafion tube. A protective cylinder is provided on the outer side of the Nafion tube, and the protective cylinder is provided with a purge gas inlet and a purge gas outlet. Sample gas inlets and outlets are provided at the left and right ends of the Nafion tube. A carrier gas inlet and a carrier gas outlet are also provided on the inner wall of the heating and insulation layer. The purge gas inlet, purge gas outlet, sample gas inlet, carrier gas inlet, and carrier gas outlet all extend outward from the inner wall to the outside of the enrichment chamber. The sample gas outlet is located between the Nafion tube and the adsorbent material.

[0005] Furthermore, the enrichment device also includes a three-way valve and a switching valve. The three-way valve is located at one end of the carrier gas inlet, and the switching valve is located between the carrier gas outlet and the time-of-flight mass spectrometer.

[0006] Furthermore, an electric heating element is provided on the side of the heating insulation layer to maintain a constant temperature after heating.

[0007] A method for integrating water removal and adsorption includes the following steps:

[0008] 1) The sample gas is purged with water through a Nafion tube before entering the adsorbent material;

[0009] 2) Heating the insulation layer and analyzing the sample.

[0010] 3) Open the three-way valve and the on / off valve to introduce carrier gas. The carrier gas will then pass the desorbed sample into the time-of-flight mass spectrometer for detection and analysis.

[0011] Furthermore, the heating temperature of the heating insulation layer is 95-110℃.

[0012] Furthermore, the adsorbent material is Carbopack B and Carboxen-1000.

[0013] Furthermore, after the sample is adsorbed, the sample gas is discharged through a three-way valve.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] This invention patent can remove water and enrich trace substances in the environment online. The device is compact and easy to operate. Moreover, the device and method are very novel, integrating water removal into the enrichment device to avoid the influence of the environment on sample detection, which is beneficial to the qualitative and quantitative analysis of samples. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of an enrichment device and method that integrates water removal and adsorption.

[0017] In the figure: 1. Enrichment chamber, 2. Heating and insulation layer, 3. Adsorbent material, 4. Nafion tube, 5. Three-way valve, 6. Switch valve, 7. Time-of-flight mass spectrometer, 8. Sample gas inlet, 9. Sample gas outlet, 10. Purge gas inlet, 11. Purge gas outlet, 12. Carrier gas inlet, 13. Carrier gas outlet. Detailed Implementation

[0018] The processing technology of the present invention will be further described below with reference to specific embodiments.

[0019] As shown in the figure, an integrated water removal and adsorption enrichment device includes an enrichment chamber and a time-of-flight mass spectrometer. The enrichment chamber comprises a heating and insulation layer 2, adsorbent material 3, and Nafion tubes 4. The inner layer of the enrichment chamber contains Nafion tubes, the middle layer contains the heating and insulation layer, and the adsorbent material is also placed in the interlayer between the heating and insulation layer and the Nafion tubes. An electric heating element is also installed on the side of the heating and insulation layer to maintain a constant temperature after heating. The heating temperature of the heating and insulation layer is 95-110℃, and the adsorbents are Carbopack B and Carboxen-1000.

[0020] The Nafion tube is surrounded by a protective sleeve, which is equipped with a purge gas inlet 10 and a purge gas outlet 11. The left and right ends of the Nafion tube are equipped with sample gas inlets 8 and sample gas outlets 9. The inner wall of the heating and insulation layer is also equipped with a carrier gas inlet 12 and a carrier gas outlet 13. The purge gas inlet, purge gas outlet, sample gas inlet, carrier gas inlet and carrier gas outlet all extend outward from the inner wall to the outside of the enrichment chamber. The sample gas outlet is located between the Nafion tube and the adsorbent material.

[0021] The device also includes a three-way valve and a switching valve. The three-way valve is located at one end of the carrier gas inlet, and the switching valve is located between the carrier gas outlet and the time-of-flight mass spectrometer.

[0022] The sample gas enters Nafion tube 4 through the sample gas inlet. The Nafion tube is purged with purge gas to remove moisture. The sample gas flows through Nafion tube 4 and exits from the sample gas outlet, diffusing into the adsorbent material 3. The sample gas is adsorbed. The heating insulation layer heats and maintains the temperature of the entire enrichment chamber, allowing the adsorbed sample to desorb. After adsorption, the sample gas is discharged through the NO end of the three-way valve. When the enrichment and desorption temperature reaches 95-110℃, the three-way valve and the on / off valve are opened, and carrier gas is introduced. The carrier gas carries the desorbed sample to the time-of-flight mass spectrometer for detection. After detection, heating is turned off for cooling. The entire enrichment and detection process is complete when the temperature drops to room temperature.

Claims

1. A water removal and adsorption integrated enrichment device, characterized in that, The apparatus includes an enrichment chamber and a time-of-flight mass spectrometer. The inner layer of the enrichment chamber contains a Nafion tube, and the middle layer contains a heating and insulation layer. An adsorbent material is also placed in the interlayer between the heating and insulation layer and the Nafion tube. A protective cylinder is provided on the outer side of the Nafion tube, and the protective cylinder is provided with a purge gas inlet and a purge gas outlet. Sample gas inlets and outlets are provided at both ends of the Nafion tube. A carrier gas inlet and a carrier gas outlet are also provided on the inner wall of the heating and insulation layer. The purge gas inlet, purge gas outlet, sample gas inlet, carrier gas inlet, and carrier gas outlet all extend outward from the inner wall to the outside of the enrichment chamber. The sample gas outlet is located between the Nafion tube and the adsorbent material.

2. The enrichment device integrating water removal and adsorption according to claim 1, characterized in that, It also includes a three-way valve and a switching valve. The three-way valve is located at one end of the carrier gas inlet, and the switching valve is located between the carrier gas outlet and the time-of-flight mass spectrometer.

3. The enrichment device integrating water removal and adsorption according to claim 1, characterized in that, The heating and insulation layer is also equipped with an electric heating element on its side, which maintains a constant temperature after heating.

4. The method for integrated water removal and adsorption as described in claims 1-3, characterized in that, Includes the following steps: 1) The sample gas is purged with water through a Nafion tube before entering the adsorbent material; 2) Heating the insulation layer and analyzing the sample. 3) Open the three-way valve and the on / off valve to introduce carrier gas. The carrier gas will then pass the desorbed sample into the time-of-flight mass spectrometer for detection and analysis.

5. The method for integrating water removal and adsorption according to claim 4, characterized in that, The heating temperature of the heating insulation layer is 95-110℃.

6. The method for integrating water removal and adsorption according to claim 4, characterized in that, The adsorbent materials are Carbopack B and Carboxen-1000.

7. The method for integrating water removal and adsorption according to claim 4, characterized in that, After the sample is adsorbed, the sample gas is discharged through a three-way valve.

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